Occupants routinely crank up the air conditioning (A/C) for extended periods of time, running down the temperature of the wall, ceiling and floor mass. When they return to the room and open the outside slider they let outside humidity into the room which condenses on these cold surfaces. Visible surfaces warm quickly eliminating any problem that could arise from the condensation but the sheet rock and concrete have thermal inertia prolonged by the insulating effect of the carpet and wall coverings and this encourages moisture that penetrates the wall covering or carpet to condense on the surface and become absorbed by the concrete or sheetrock as condensation. These wet, humid, dark areas then harbor the conditions that are ideal for mold and mildew growth. Odor and degradation of carpet and wall covering are next. In some individuals, the presence of mold spores can also cause respiratory problems, and some mold spores are poisonous to all individuals.